The invention relates to an ignition device for an Otto engine.
One ignition device known in the art is disclosed in DE 10 2010 007 007 A1. With ignition devices of this type, it is possible to generate a high voltage for a spark plug from an on-board power supply system voltage of a vehicle battery. The ignition coil of such an ignition device operates here by the principle of a transformer, that is to say it has a primary winding that is fed by a vehicle battery, and a secondary winding that is connected to a spark plug.
A thermal loss caused by the currents involved in the voltage transformation and by magnetic fields leads to a considerable temperature load of ignition devices. In addition, there is also a considerable thermal loss in the control circuit of the ignition device, for example, caused by power transistors, which are used to switch the currents.
So that the control circuit of an ignition device can function correctly, it has to be cooled or the thermal loss produced by the control circuit has to be removed from the housing of the ignition device. For this purpose, it is known from DE 10 2010 007 007 A1 to fasten a metal thermal dissipation element to power transistors of the control circuit, said thermal dissipation element protruding from the housing and being fastened by a flange on an engine block so that the coolant of the engine can also cool the thermal dissipation element.